Janis Joplin has had a piece of Randy Johnson’s heart ever since he heard her Cheap Thrills album when he was 5 years old.

“Janis had always been part of my conscious and subconscious,” says Johnson, the writer and director of One Night With Janis Joplin, a theatrical re-creation of a Joplin concert, now onstage at the Pasadena Playhouse in Southern California and soon to be on view in other cities.

When Johnson was growing up in the Los Angeles suburb of Culver City, his music-loving parents had a substantial record collection. Cheap Thrills, the 1968 release that includes Joplin’s version of George and Ira Gershwin’s “Summertime,” is one of the first albums he recalls hearing. So Johnson, who has a long résumé of theatrical and TV projects, was most receptive when, a few years ago, Jeff Jampol, the manager of Joplin’s estate, asked if he’d like to put together a musical based on the late singer’s life and career.

Jampol arranged for Johnson to meet with Joplin’s brother and sister, Michael and Laura. Johnson talked with them for hours, and he learned that Joplin had talents beyond music; she was a gifted painter, she designed her own costumes, and she was totally in control of her career and image. The family also gave him access to Joplin’s unpublished writings.

He took all this information home with him and pondered how to put the show together. Johnson, who has written, directed, or produced shows on musical figures as diverse as Patsy Cline, Elvis Presley, Conway Twitty, and the duo of Louis Prima and Keely Smith (his godmother), wanted to make sure he wasn’t repeating himself in any way.

Mary Bridget Davies as Janis Joplin

Then one night he thought about the singers who inspired Joplin — blues and R&B artists such as Bessie Smith, Odetta, Etta James, Nina Simone, and Aretha Franklin. “I realized that Janis’s influences were my influences,” he says. “I thought, How great would it be if Janis got to sing duets with her influences?” The following morning he got up, made a pot of coffee, and wrote the show in the next 18 hours. It’s undergone very few revisions since then, from its premiere in Portland, Ore., in 2011, through productions in Cleveland and Washington, D.C., last year, to the current staging in Pasadena.

In addition to Joplin, played by Mary Bridget Davies, and her band, the show has a character called the Blues Singer, played by Sabrina Elayne Carten. “I created the character of the Blues Singer as Janis’s alter ego,” Johnson says, so audiences can see where Joplin found her inspiration and where she took it, and also to recognize the contributions of these important African-American artists. Joplin, he notes, broke color barriers, frequently singing onstage with black performers.

The production is constructed as a concert by Joplin, and “it’s up to the audience whether it’s her last concert or a dream concert,” Johnson says. While the singer is said to have had love affairs with both women and men, the show doesn’t go into that aspect of her life, as she would not have discussed that onstage, he says. Nor does it deal with her drug use (she died of an accidental overdose in 1970, at age 27).

But Johnson, who is gay, sees Joplin as universally appealing. “People were drawn to her essence,” he says. “She appealed to men and women as a true American original. … She made it OK for women to think as individuals, for people, straight or gay, simply to be who you are.”

That was also his advice to Davies, who has been with the show since the Cleveland production, originally as understudy for the Joplin role. “I told her just be yourself,” he says, not to try to imitate Joplin, as the role called for authenticity, not imitation. She brought plenty of authenticity, he says; upon seeing her perform, he and the rest of the show’s creative team “felt like we were at Woodstock.” Carten, who has been in the role of the Blues Singer since the Portland staging, is equally authentic, he adds: “I would describe them both as forces of nature.”

In addition to beloved Joplin tunes such as “Piece of My Heart,” “Mercedes Benz,” “Me and Bobby McGee,” “Ball and Chain,” and “Summertime,” the show features a song that was written for Joplin but that she never got to record, “I’m Gonna Rock My Way to Heaven.” Jerry Ragovoy, who cowrote several other songs recorded by Joplin, such as “Cry Baby” and “Try (Just a Little Bit Harder),” and penned the Rolling Stones’ “Time Is on My Side,” wrote “I’m Gonna Rock My Way to Heaven” in collaboration with Jenny Dean, with input and notes from Joplin, but the singer died before she could record it. So it premiered in One Night With Janis Joplin, and Ragovoy got to see the song performed in the Portland production, shortly before his death, Johnson notes.

“I never wanted this to be a jukebox musical, because it’s not,” Johnson adds. “It’s a rock and roll biographical event. … I look at the show as the journey of the spirit of Janis Joplin.”

Johnson himself journeyed into a show business career because “I had no choice,” he says. His parents were not in showbiz — his father, Paul, was an aircraft engineer, his mother, Selma, a nurse — but they loved it. They exposed their son to a wide range of music, and they even danced as members of the studio audience on The Lawrence Welk Show. Keely Smith came into his life because she had gone to high school with his mother, and who calls her “one of the finest human beings on our planet.”

Johnson started out as an actor, then was recruited for behind-the-scenes jobs, such as producing and serving as assistant director of the West Coast premiere of Larry Kramer’s The Normal Heart, starring Kathy Bates and Richard Dreyfuss, in Los Angeles in 1985. “I loved being on the other side of the table,” Johnson recalls. Outside of theater and TV, his credits include producing, with Bernie Taupin, the Commitment to Life benefit for AIDS Project Los Angeles for several years, and producing events for Howard Dean’s presidential campaign in 2004. He received the Crystal Apple Award for his work on behalf of APLA and was named Volunteer of the Year by AIDS support group L.A. Shanti.

The never-closeted, currently single Johnson lives in West Hollywood with his beloved Scottish terrier, Symon, who has accompanied him to many hotel rooms during the travels of One Night With Janis Joplin. After the Pasadena run, the show is scheduled to be staged at the Milwaukee Repertory Theatre, the Zach Theatre in Austin, and the San Jose Repertory Theatre in California, and to have an encore production at the Arena Stage in Washington, D.C.

Johnson stresses that the show is a team effort, thanking Jampol, the Joplin family, and his producers, Daniel Chilewich and Todd Gershwin (he’s the great-nephew of George and Ira). “This dream and vision of mine would not have come to life without those people,” he says.

Johnson has a few more visions to realize; he’s working on a memoir, titled Adventures in Hotel Crazy, and he’s going to direct Smokey Joe’s Café, the musical based on the songs of Jerry Leiber and Mike Stoller, next spring at the Arena Stage.

In the meantime, he’s happy to help Janis Joplin live on. While she accomplished a great deal in her short life, she had much more to give, he says: “I do believe that she would have gone on for many years changing the shape of American music.”

One Night With Janis Joplin runs through April 21 at the Pasadena Playhouse; click here for tickets and information. For more information on Johnson, go to RandyJohnson1.com.